A total of 114 individuals of 17 resident and 10 migrant species captured at a rainforest study site in the Tuxtla Mountains of southern Veracruz, Mexico, were displaced to a second rainforest site 2.5 km distant. Return rates to point of capture were high for both groups (73% for resident species versus 74% for migrants). These comparable rates, when considered with evidence that residents can accumulate large fat reserves, indicate that resident species possess key adaptations necessary for migratory movement.

Un total de 114 individuos pertenecientes a 17 especies residentes y 10 migradoras capturados en un enclave de selva húmeda en las montañas de Tuxtla al sur de Veracruz, México, fueron trasladados a un segundo enclave de selva humeda situado a 2.5 km de distancia. Las tasas de retorno al punto de captura fueron altas para los dos grupos (73% para las especies residentes y 74% para las migradoras). Teniendo en cuenta que los residentes pueden acumular grandes reservas de grasa, la similitud de estos resultados indica que estas especies poseen las adaptaciones necesarias para el movimiento migfatorio.

Tourism development is one of the main contemporary drivers of habitat loss and fragmentation within the Caribbean Islands biodiversity hotspot. In Saint Lucia, construction of a hotel and golf course within coastal dry forest is directly threatening the largest known subpopulation of the Endangered White-breasted Thrasher Ramphocinclus brachyurus. Understanding how the species is responding to ongoing landscape change and identifying priority sites for conservation are imperative for planning its long-term conservation. In this study, a four year White-breasted Thrasher monitoring dataset (2006–2009) and landscape-scale environmental variables were used to: a) identify, characterise and map spatio-temporal patterns of White-breasted Thrasher encounter rate (an abundance proxy) within and outside the tourist development site; b) determine landscape-scale environmental variables that influence such patterns, and c) produce an island-wide predictive map of potentially suitable habitat. Observed patterns in encounter rates within and outside the development site were consistent with thrashers being displaced from cleared areas of forest and crowding into intact forest patches to the north and west of the golf course. A year after the period of the most extensive habitat clearance, White-breasted Thrasher numbers declined markedly leading to a 55% reduction in encounter rate within the development site over the four years of the study. The habitat suitability model predicted that a range of sites outside of the known geographic range of the thrasher are potentially suitable, some of which merit further surveys for potentially undetected populations. Given these findings, it is vital that patches of suitable dry forest adjacent to the tourist development are protected and contiguous natural habitat inside the tourist development is preserved.

Reintroductions aim to re-establish a viable population within the indigenous range of living organisms, especially of threatened species. The population of the Asian Crested Ibis Nipponia nippon, a well-known ‘Endangered’ bird species, has increased over 100 times since wild populations were rediscovered in 1981, and several reintroduction projects were subsequently carried out in its former range. An experimental release of the Asian Crested Ibis was conducted in Qianhu National Wetland Park located in the southern part of the Loess Plateau, China. It is vitally important to monitor released birds (at least their survival and breeding), to inform subsequent releases in other suitable sites. During extensive post-release monitoring, data on capture-recapture and reproductive status were obtained using banding, radiotelemetry, and field observations. Using the Cormack-Jolly-Seber (C-J-S) model, the average annual survival rates were estimated to be 0.569 (95% CI: 0.353–0.762) for released individuals and 0.643 (95% CI: 0.038–0.987) for all individuals. From 2014 to 2018, a total of 14 breeding pairs produced 28 eggs and 10 fledglings with successful reproduction of the second generation. The mean clutch size was 2.07 ± 0.25 (n = 29), and the breeding success was 34.5%. Predation and poor habitat quality have been shown to be the main factors affecting the reintroduced population at establishment stage. Some management suggestions at the metapopulation and ecosystem levels, including further release, predator control and habitat improvement, have been proposed.

An analysis of the extent of overlap between habitats of the Egyptian Vulture Neophron percnopterus during summer and winter in Iran, and Iranian protected areas, discovered slight overlap between the two. Our study aimed to survey suitable habitats of the Egyptian Vulture during summer and winter in Iran using MaxEnt, a species distribution modelling method, and compare the results with the locations and span of protected areas. Model fitness was assessed using the area under the ROC-plot and True Skill Statistics. We found that habitat suitability in Iran varies for the Egyptian Vulture during summer and winter. Summer visitors are scattered in the north and west of Iran, concentrated along the Zagros and Alborz mountain ranges. Winter visitors and residents are scattered in coastal areas in the south. Habitat protection for winter visitors was the greatest, with 10% of suitable habitat covered, while less than 10% of suitable habitat for residents and summer visitors fell within protected areas. The Egyptian Vulture is categorised as ‘Endangered’ on the IUCN Red List. Different environmental factors influence the suitability of habitat for the species. While some factors such as NDVI and anthropogenic disturbance influence all visitors in a similar way, the effects of others such as elevation and distance from protected areas vary for summer and winter visitors. Since designation of protected areas in Iran is mainly determined by the distribution of mammal species, protection of bird habitats is often overlooked. Suitable habitat for the species should be considered when selecting protected areas in future.

Vulture populations are declining steeply worldwide. Vulture ‘restaurants’ or feeding stations are a tool for maintaining and monitoring numbers, but individual species may be disadvantaged by the effects of carcass distribution, carcass size and interspecific aggression. To test the degree to which restaurants give opportunities for each species to access the food provided, we studied behaviour and morphology in three Critically Endangered species of vulture in Cambodia: the gregariously breeding and feeding White-rumped Vulture Gyps bengalensis and Slender-billed Vulture G. tenuirostris, and the solitary Red-headed Vulture Sarcogyps calvus. We video-recorded attendance time, attendance order and dominance behaviour at different-sized carcasses. Interspecific aggression at carcasses was least frequently shown by the ‘small’ White-rumped Vulture. The relatively ‘large’ Slender-billed and ‘medium’ Red-headed Vultures showed aggression more regularly and at similar levels. However, the latter avoids conflict by waiting until Gyps vultures are no longer crowding at the carcass, although its arrival at carcasses was correlated with total number of vultures present. While more numerous than Red-headed, the two Gyps vultures are more dependent on large carcasses, which increases their vulnerability to further declines in wild large ungulate species. Body size, number of individuals, hunger levels and carcass size and availability all influence carcass attendance behaviour. An increase in the number and spatial distribution of restaurants as well as of carcass size range could boost numbers of all vulture species.

Monoculture plantations of exotic Caribbean pine Pinus caribaea have been planted extensively in many tropical countries, but little is known about the bird communities inhabiting them. From October 1995 to September 1996, we compared bird populations in a 37-ha stand of mature Caribbean pine forest (planted in 1972) with an adjacent, similar-sized stand of native broad-leaved forest at Mount Saint Benedict, Trinidad, West Indies. Ten censuses, each including 10 fixed-radius point counts (25 m radius, 10 minutes duration), were conducted simultaneously during different months of the year in each habitat. Both species richness and species diversity were significantly lower in the pine forest, but the overall abundance of individual birds did not differ between the two forests. Seasonal variation in bird populations was more pronounced in the pine forest, where fewer birds (and presumably food resources) were present during the dry season. The pine forest bird community was dominated by forest edge specialists and the native forest by forest interior specialists at both the individual and species levels. At the individual level, nectarivores, aerial foragers and understorey foragers were proportionately more common in the pine forest; insectivores and canopy foragers were more common in the native forest. At the species level, more aerial foragers occurred in the pine forest and more understorey foragers in the native forest. The diversity of bird communities in pine plantations may be promoted by increasing habitat heterogeneity.

Knowledge of a species’ potential distribution and the suitability of available habitat are fundamental for effective conservation planning and management. However, the quality of information on the distribution of species and their required habitats is highly variable in terms of accuracy and availability across taxa and regions, particularly in tropical landscapes where accessibility is especially challenging. Species distribution models (SDMs) provide predictive tools for addressing gaps for poorly surveyed species, but they rarely consider biases in geographical distribution of records and their consequences. We applied SDMs and variation partitioning analyses to investigate the relative importance of habitat characteristics, human accessibility, and their joint effects in the global distribution of the Critically Endangered Blue-throated Macaw Ara glaucogularis, a species endemic to the Amazonian flooded savannas of Bolivia. The probability of occurrence was skewed towards more accessible areas, mostly secondary roads. Variability in observed occurrence patterns was mostly accounted for by the pure effect of habitat characteristics (76.2%), indicating that bias in the geographical distribution of occurrences does not invalidate species-habitat relationships derived from niche models. However, observed spatial covariation between land-use at a landscape scale and accessibility (joint contribution: 22.3%) may confound the independent role of land-use in the species distribution. New surveys should prioritise collecting data in more remote (less accessible) areas better distributed with respect to land-use composition at a landscape scale. Our results encourage wider application of partitioning methods to quantify the extent of sampling bias in datasets used in habitat modelling for a better understanding of species-habitat relationships, and add insights into the potential distribution of our study species and opportunities for its conservation.

Lake Junín is famous for the abundance and diversity of breeding, staging and wintering waterbirds. The lake supports the entire world population of three species or subspecies: Junín Grebe Podiceps taczanowskii, Junín Rail Laterallus tuerosi and the endemic subspecies of the White-tufted Grebe Rollandia rolland morrisoni. Surveys undertaken in the 1930s, 1960s, 1970s and 1980s confirmed the lake’s importance in the Andes, however there has been no recent assessment of its waterbird community. We undertook waterbird counts between 6 and 20 February 2014 from the lakeshore and by boat. Despite using differing survey methods, we nevertheless conclude that the relative abundance of waterbird species has changed dramatically compared to earlier counts. Most notably, the Junín Grebe has experienced a major decline since the 1930s when the species was considered extremely abundant and another native fish-eating species the White-tufted Grebe also appears to have declined. In contrast the Northern Silvery Grebe Podiceps juninensis, classified as ‘Near Threatened’, has apparently become more abundant. Numbers of Puna Teal Spatula puna and Common Gallinule Gallinula galeata seem to have crashed, presumably reflecting the general loss of submerged vegetation. In spite of a major decline in waterbirds overall, the Junín area holds numbers of migratory shorebirds, perhaps as a consequence of local hunting restrictions and awareness campaigns. Lake Junín is a candidate for listing on the Montreux Record under the Ramsar Convention as a wetland showing serious change in ecological character. Management planning should proceed to balance conflicting interests at the lake. Actions to re-establish a clear water column by reducing eutrophication (from settlements in the catchment) as well as sedimentation and heavy metals (from upstream mining) will contribute to improving ecological functions and to secure waterbirds including the endemics.

The Anjouan Scops Owl Otus capnodes, not recorded with certainty since about 1886, was rediscovered in June 1992. It has usually been treated as a race of Madagascar Scops Owl Otus rutilus but, judging from plumage and especially voice, it is a distinct species. It is found only in the remaining patches of upland forest (above 800 m) on Anjouan (Ndzuani), Comoro Islands, where the population is estimated to be at least several tens of pairs, probably between 100 and 200 pairs. The species is highly endangered by accelerating forest clearance and capture for food by the huge and increasing human population. Long-term environmental programmes are essential but may be too late to save this and other endangered species on Anjouan. Species-specific actions are needed: for the owl, a translocation to the neighbouring island of Moheli should be investigated.

La chouette Scops d'Anjouan Otus capnodes, qui n'avait pas été observée avec certitude depuis environ 1886, a été redécouverte en juin 1992. Elle était habituellement considérée comme appartenant à la race des chouettes Scops de Madagascar Otus rutilus, mais à en juger par son plumage et surtout par sa voix, c'est une espèce différente. Elle n'existe que dans les restants de forêts d'altitude (plus de 800 mètres) en Anjouan (Ndzuani), dans les lles Comores, où la population est estimée à au moins plusieurs dizaines de couples, probablement entre 100 et 200 paires. L'espèce est fortement menacée par l'accélération de la déforestation et la capture de ces oiseaux pour l'alimentation d'une population humaine très nombreuse et croissante. Des programmes de conservation de l'environnement à long terme sont essentiels, mais arriveront peut-être déjà trop tard pour sauver cette espèce et d'autres espèces menacées en Anjouan. Des actions spécifiquement centrées sur chaque espèce sont nécessaires: pour la chouette, la possibilité d'un transfert sur l'île voisine de Mohéli devrait être examinée.

We present the first study of the spatial and temporal dynamics of raptors and large soaring birds from the Isthmus of Tehuantepec, Mexico. Using systematic migration counts from multiple localities in the southern states of Oaxaca and Chiapas, as well as observations of their flight trajectories during eight consecutive years (2007–2014), we describe the magnitude of these movements, their geographic extent, and the phenology of the most abundant species in both spring and fall seasons. The most abundant species were Turkey Vulture Cathartes aura, Swainson’s Hawk Buteo swainsoni, Broad-winged Hawk Buteo platypterus, Wood Stork Mycteria americana, American White Pelican Pelecanus erythrothynchos, Franklin’s Gull Leucophaeus pipixcan, and American Kestrel Falco sparverius. In spring, the seasonal average magnitude of migration was over 28,000 birds, while in autumn the average was over one million. The aggregated seasonal phenologies recorded illustrate a variety of migration patterns. The inter-annual variation is lower in autumn than in spring. Migrating raptors and other soaring birds did not seem to use any topographical feature as a leading line for their movements in spring, while in autumn they did. We estimated the main axis of spring flights to run along a SE–NW vector, while autumn migration follows a WNW–ESE general trajectory. Our results place the isthmus as one of the five most important sites in the world for raptors and soaring migrants. Sustaining annual migration counts at these sites is of high importance to track substantial portions (> 90%) of the global population of Turkey Vulture and Swainson’s Hawk, as well as over 10% of the global population of Broad-winged Hawk. Autumn migration counts have the potential for long-term population monitoring.

The Yabelo–Mega region of southern Ethiopia's Borana region holds two threatened endemic and restricted-range species, the White-tailed Swallow Hirundo megaensis (‘Vulnerable’) and Ethiopian Bush-crow Zavattariornis stresemanni (‘Endangered’). Concern about these species’ conservation status has recently increased owing to rapid alterations to their thornbush savanna habitat. This six-week field study aimed to identify the specific habitat requirements of each species, with a view to understanding how they are likely to be affected by these changes, and to provide baseline quantitative abundance data using simple and repeatable methods. White-tailed Swallows were recorded on an overall 4.7% of transects and point counts, and in all habitats (including villages and farmland) except broadleaved Combretum–Terminalia woodland. Line transects indicated that swallows avoided dense scrub and tree cover, but this was not detected during point counts. Bush-crows were recorded on an overall 16.6% of transects and point counts, and like swallows showed a strong preference for thornbush (Acacia and Commiphora) over broadleaved woodland, avoided dense scrub cover, and were particularly frequent in the vicinity of villages. During point-counts, bush-crows were more frequently encountered inside the nominally protected Yabelo Sanctuary, whereas the reverse was true for White-tailed Swallows. Recent concern about dramatic declines in bush-crow numbers revealed by roadside counts may have been exacerbated by habitat alteration along roads alone, but the species remains under threat from habitat transformation through agricultural expansion, tree felling and bush encroachment.

Hinde's Babbler Turdoides hindei is a globally threatened Kenyan endemic, which during the 1990s, was known from just seven localities. Based mainly on surveys undertaken in 2000–2001, we estimate the species's global population size and compare recent changes in its “extent of occurrence” and “area of occupancy”. Historically, Hinde's Babbler has been recorded from c. 40 10 × 10 km squares; 27 pre-1980 and 19 subsequently, suggesting that its area of occupancy has declined by about 30%. In contrast, its extent of occurrence has declined by only 8%, this measure being less sensitive to the balance of gains and losses occurring near the centre of its range. During surveys in 1994 and 2000–2001, 157 groups were located, containing 665 birds, 75% of which were found at two intensively cultivated sites. Some 97% of birds were located in, or adjacent to, five Important Bird Areas, but only 8% were found within legally protected areas. Two extrapolated population estimates are presented, based on the number of birds likely to have been missed at survey sites, and the species' area of occupancy. These suggest that the global population of Hinde's Babbler is likely to fall within the range of 1,500–5,600 birds.

Censuses were conducted from 15 June to 6 July and from 15 to 24 October 2003 throughout Lake Titicaca to determine the current distribution and abundance of the Titicaca Flightless Grebe Rollandia microptera. We surveyed 22 of an estimated 25 local population distribution ranges. We defined these as shallow offshore feeding areas in combination with coastal beds of tule-rushes (Schoenoplectus tatora). At this large spatial scale we found variously sized populations of grebes in all 22 of the areas surveyed and a negative correlation between the total area of tule-bed within each area and grebe density. Absolute counts of grebes pooled across all sites produced a total of 2,582 individuals on Lake Titicaca. Given that some sites were either partially surveyed or not surveyed at all we feel that this is an underestimate of the total lake population. Limitations in methodologies used precluded the classification to development stage of approximately 43% of the individuals counted. Among the remaining 57% of the individuals counted we identified 732 mature adults within the total population of Lake Titicaca. When combined with information from other sources and current knowledge of habitat fragmentation our results support the classification of the species in the IUCN Red List as Endangered under criterion C2a. Of 20 local fisherman interviewed on the Bolivian side of Lake Titicaca, 90% confirmed that individuals of Titicaca Flightless Grebe incidentally drown in their fishing nets although responses varied from weekly to monthly estimates of by-catch. Although this study provides the first estimate of the total population of Titicaca Flightless Grebes on Lake Titicaca, a standardized monitoring programme will be required in order (1) to provide a baseline for the interpretation of future population trends in the context of impacts generated by human activities and (2) to aid in future management decisions for the long-term conservation of the species.

The evolution of 40 wintering areas of Grus grus in the south-west of the Iberian Peninsula has been studied, including the traditional wintering places of this species on its western route. Eight of these areas harboured 50% of the whole population using this route, and none of the 40 areas showed a decline in the number of birds during the study period. At present the number of cranes in each area is much greater than in the 1979–1980 winter. No geographical trends have been observed regarding the magnitude of the increase, which is closely related to that observed for the whole Spanish and Palearctic populations. Despite the emergence of some new wintering areas, the magnitude of the increase is greater in more southerly parts of the range. This may be a consequence of greater diversity and availability of food in these latitudes. The influence of enhanced international protection and agricultural food sources on the appearance of new wintering areas is discussed.

Over the last decades, European farmland birds have strongly declined, mainly driven by agricultural intensification. The Ortolan Bunting Emberiza hortulana has suffered one of the most severe declines among farmland specialists. In order to maintain viable populations of the species in the long run, there is a vital need for evidence-based conservation measures. The main goal of this study was to detect the key drivers of breeding-territory selection and mating success of the species in an agricultural landscape in central Europe. We found that the landscape structure within the territories of Ortolan Bunting breeding pairs strongly varied from the overall habitat availability in the study area on both the territory and home-range scales. However, the environmental conditions also differed between the territories of breeding pairs and those of unpaired males. While landscape structure played an important role in breeding-territory selection, it had only weak effects on mating success. In contrast, crop type and vegetation height at potential nesting sites were important drivers of mating success. Overall, our study revealed that Ortolan Bunting has very complex breeding-habitat requirements. Only heterogeneous agricultural landscapes where (1) suitable song posts, (2) appropriate nesting sites, and (3) sufficient foraging habitats occur in close proximity are suitable for breeding. According to the findings of our study, agri-environmental schemes should primarily facilitate low-intensity farming practices that promote landscape heterogeneity, provide suitable nesting sites, and sustain a high abundance of invertebrate prey in farmlands.

In July and August 1994, we surveyed two areas in the south of the Cordillera de Colán, Amazonas department, Peru, above the north bank of the río Utcubamba. We found a high rate of deforestation, with trees being felled for timber, forest being cleared for the cultivation of cash crops, and elfin forest being burned for pasture. Most of the forest on the mountain range may have been cleared in 10 years. We recorded a number of important bird species, highlighting the significance of the area for the conservation of biodiversity; globally threatened birds included Peruvian Pigeon Columba oenops, Military Macaw Ara militaris and Royal Sunangel Heliangelus regalis. Elfin forest is under particular threat in the area, but probably still holds species such as Long-whiskered Owlet Xenoglaux loweryi. We recommend that a protected area containing areas of cloud-forest and elfin forest be established on the Cordillera de Colán.

In 2013 a prediction was made that the South-East Asian subspecies of Bengal Florican Houbaropsis bengalensis blandini would be extinct within 10 years. In 2018 we conducted a survey in the Tonle Sap floodplain, Cambodia, of the last population of Bengal Florican in South-East Asia. We found that the rate of decline in displaying males was 55% over five years, a decline comparable to that recorded between 2005–2007 and 2012. The estimated number of displaying males in 2018 was 104 (95% CI: 89–117), down from 216 (156–275) in 2012. We also conducted surveys by flushing birds in the non-breeding season, which indicated that the sex ratio of males to females is 3:1. We therefore estimate that the total population of adult Bengal Floricans in Cambodia in 2018 was 138 (119–156), making H. b. blandini the most threatened bustard taxon. The number of sites that support displaying male Bengal Floricans was reduced from 10 to four between 2012 and 2018. Between 2012 and 2018 we monitored numbers of displaying males in most years at the sites that support 80% of the total population. The only site where numbers of birds are stable is Stoung-Chikraeng Bengal Florican Conservation Area, where there were 44 (25–63) displaying males in 2018. This is the only site that has an ongoing NGO-government conservation programme. Our data indicate that Bengal Floricans are lost from sites when the area of grassland falls below 25 km2. We found evidence that displaying male Bengal Floricans abandon display territories when grassland is lost, this also creates hope that they may disperse and could colonise newly created habitat. All remaining sites that support Bengal Floricans in Cambodia are imperilled and we outline what must be done to reduce the possibility that H. b. blandini will be extinct by 2023.

The 2011 breeding results of the Lesser Flamingo Phoeniconaias minor at its only West African colony, in Aftout es Saheli, south-west Mauritania, are presented. Several breeding attempts have been documented since the second half of the 19th century although no successful breeding, in terms of fledged juveniles, was recorded until 2010. Adverse hydrological dynamics, easy access to the colony by predators, and disturbance and direct mortality caused by poachers led to the failure of all previous breeding attempts. In 2011 the breeding colony was monitored and a number of major threats were identified and averted. Management interventions consisted of deterring and trapping predators (jackals Canis adustus and C. aureus and warthog Phacochoerus africanus) around the colony and preventing the killing of flamingos by poachers. As a result, 4,800 Lesser Flamingos and 10,200 Greater Flamingos Phoenicopterus roseus incubating individuals, as well as about 14,000 chicks of both species, were recorded. It was not possible to prevent the death by predation or other natural causes of 4,672 juveniles of both species after the wetland dried up, so the final estimated number of fledged juveniles was 10,000. The field work allowed us to collect information on hydrological dynamics and to propose conservation measures matching Lesser Flamingo ecological requirements. Similarly, we identified the most sustainable measures for deterring predators, with the aim of including them in the management of the wetland.

The Congo Grey Parrot Psittacus erithacus has experienced a severe population breakdown in recent decades. The rainforests of the Korup region in Southwest Cameroon may harbour a large population of this species, but density and population estimates from this area remain controversial. Before the 2016 breeding season, we surveyed Grey Parrots along transects (621.1 km survey effort) in three adjacent landscape types: primary forest in Korup National Park (KNP), smallholder agroforestry matrix (AFM), and industrial oil palm plantation (OPP). We also collected information on the trees used for nesting, feeding and roosting. Using Distance analysis, we estimated relatively low densities of stationary flocks, ranging from 0.30 ind./km2 in KNP, over 0.82 ind./km2 in OPP to 2.70 ind./km2 in the AFM. Parrots were observed feeding or roosting in 17 tree species, of which 15 were located in AFM alone. Feeding was most often observed on cultivated Elaeis guineensis and Dacryodes edulis, but never in maize. The detected parrot densities probably reflect declines within the period 2008–2016, suggesting that the species’ recent IUCN uplisting to ‘Endangered’ and transfer to CITES Appendix I was indeed justified. Our results also suggest that traditional smallholder agroforestry may play a role in habitat conservation strategies, since these forms of cultivation may maintain important breeding and feeding opportunities for Congo Grey Parrots.

We investigated the decline and current status of the Black Kite Milvus m. migrans Boddaert 1783 and the endemic and distinct Red Kite (Cape Verde Kite or Cape Verde Red Kite) Milvus milvus fasciicauda Hartert 1914 on the Cape Verde archipelago. In 1996 and 1997, the first census of both kites on the entire archipelago (Hille 1998) revealed that fewer than 10 individuals of each species still existed and that extinction of all kites on Cape Verde was imminent. As expected from this first survey, the tiny island populations of kites further declined and only two individual Red Kites and one Black Kite were found in 1999. Both populations are expected to become extinct very soon. The presumed causes of extinction such as indirect poisoning, lack of food in a changing landscape, and human persecution are discussed.